High frequency hydraulic actuated jaw crusher



HIGH FREQUENCYY HYDRAULIC ACTUATED JAw cRusHER Filed Oct. 22, 1965 C. E. 4MAY June 4, 1968 2 Sheets-Sheet l INVENTOR. CLINTON E. MAY

A40/Mk ATTORNEY June 4, 1968 c. E. MAY 3,386,667

HIGH FREQUENCY HYDRAULIC ACTUATED JAW CRUSHER Filed Oct. 22, 1965 2 Sheets-Sheet 2 FEEDA CK TRANSDI/CE' FEEDBACK TANSI/CER' INVENTOR. CL/NTO/V E. MAY

Hua M ATTORNEY United States Patent O 3,386,667 HIGH FREQUENCY HYDRAULIC ACTUATED JAW CRUSHER Clinton E. May, 649 E. Pleasant St., Amherst, Mass. 01002 Filed Oct. 22, 1965, Ser. No. 501,559 1 Claim. (Cl. 241--36) ABSTRACT F THE DISCLOSURE A jaw type crusher including a pivotally mounted jaw adapted to pivot about its upper region and hydraulically operated to and from a crushing position. The hydraulic actuator is in the form of a piston motor that is double acting and that is controlled for relatively high frequency operation by means of a hydraulic and electrodynamic control device.

This invention relates generally to jaw crushers of the type utilizing a single or a pair of pivoted jaws with the invention being concerned with an improved crusher using a hydraulic drive mechanism for the power actuation of the jaw or jaws.

In the conventional jaw crusher of this type the jaws are usually mounted at their upper regions on an eccentric with a toggle being provided at the lower region of the jaw. Through the action of the eccentric, the jaw is moved to and from its innermost crushing position. These jaw crushers are very powerful but because of the mass of the structure, and particularly the eccentric drive mechansm, the frequency at which they are capable of operating is relatively low resulting in limited productivity. With the present invention in lieu of this conventional type of construction there is provided a hydraulic actuator for the jaw. The jaw is pivotally mounted adjacent it-s upper region with the hydraulic actuating mechanism being connected with the lower region of the jaw and effective to pivot the jaw about its pivotal mounting. The crusher may be of the type which has a pair of opposed jaws or it may have only a single jaw which is moved toward and away from a fixed jaw. In the preferred em- Ibodiment the hydraulic actuator includes a double acti-ig piston which is controlled by a hydraulic spool type power valve. This valve in turn is controlled by a spool type pilot valve with the pilot valve being actuated through electric mechanism that includes an electro-dynamic driver and an oscillator or signal generator which provides a signal that, after suitable amplification, controls the driver. The pilot and power valve are of course connected with a suitable hydraulic system including a relief, pump and supply means so that hydraulic fluid under pressure may be supplied to and bled from the valves and piston. The pilot valve is effective to reciprocate the spool power valve at the same frequency at which the pilot valve is operated. The power valve is in effect a hydraulic amplifier and it effects a supply and return of iiuid pressure to the piston to cause actuation of the piston at this same frequency. With this mechanism a high frequency of operation of the crusher jaw is obtained while at the same time great power can be exerted. With this increase in frequency over the conventional design there is an increase in productivity and a better crushed product cubicity. Furthermore the hydraulic actuating mechanism imparts a higher impact velocity to the crusher jaw and therefore in turn to the product thereby more readily fracturing hard materials.

Accordingly it is an object of the present invention to provide an improved jaw crusher.

A further object of the invention is to provide an improved jaw crusher wherein a jaw is pivotally mounted 3,386,667 Patented .lune 4, 1968 ice actuating mechanism for powering the operation of the crusher.

A still further object of the invention is to provide an improved jaw crusher wherein a jaw is pivotally mounted at its upper region and a hydraulic actuator is connected with the lower region to power the jaw.

Other and further objects of the invention will become apparent to those skilled in the art as the description proceeds.

With the aforementioned objects in view, the invention comprises an arrangement, construction and combination of the elements of the inventive organization in such a manner as to attain the results desired, as hereinafter more particularly set forth in the following detailed description of an illustrative embodiment, said embodiment being shown by the accompanying drawings wherein:

FIG. l is in the nature of a vertical :section of a jaw crusher embodying the present invention. This view is somewhat schematic in nature with unnecessary elements having been removed and with the control for the hydraulic drive being depicted in block diagram form; and

FIG. 2 is a sectional view of the hydraulic drive per se.

Referring now to the drawings wherein like reference characters are used throughout to designate like elements, the illustrative and preferred embodiment of the invention as depicted therein includes the jaw 10 pivotally mounted at its upper region with there being provided for this purpose bearing 12 disposed about the stationary shaft 14. This shaft is securely mounted within the frame 16 and also mounted in this frame, in the preferred embodiment, is the stationary jaw 18. As is conventional with this type of crusher the material to be crushed iS supplied intermediate the stationary jaw 18 and the movable jaw 10 through the relatively large opening at the upper end of these jaws. The movable jaw 10 is moved toward and away from the stationary jaw 18 with relatively great force such that the material is crushed and thereby substantially reduced in size with the crushed material passing from between the jaws Iat the lower region thereof.

As embodied in the invention the movable jaw 10 is oscillated about its pivotal mounting with this oscillation being effected by the electro-hydraulic exciter designated generally 20 in FlG. l and including the hydraulic piston 22 which is `connected with the lower region of the movable jaw 20 and is reciprocated through a predetermined Iamplitude at a predetermined frequency. As shown in FIG. l the hydraulic piston is mounted within a suitable housing which is, in turn, pivotally connected with the frame 16 through the pivotal support 24 and is also pivotally connected at 26 with the lower region of the movable jaw 10. The electro-hydraulic actuator includes means for generating an electrical signal of a predetermined frequency with this being identified in the block diagram as a combination of signal generator and positioned and pulse inputs. This electrical signal is suitably amplified by means of a servo control amplifier and a power amplilier. This signal is combined with feedback signals from the hydraulic actuator in order to provide for frequency stabilization. The thus amplified signal is the drive signal for a small electro-dynamic exciter which in turn drives the first spool of a two-stage servo valve. The pilot stage of this servo valve transforms the electrical variations into variations of fluid flow with these variations in turn being reproduced by the hydraulic power stage of the valve.

This latter stage acts as the hydraulic amplifier.

The primary feedback originates from the power valve. This feedback signal is compared with the source signal in a summing junction ahead of the servo control amplifier. This error signal then goes to the control amplifier and is then fed to the servo valve in an attempt to reduce the error to zero. The power val-ve is the best place to observe or locate the output of the system since it measures the power signal.

The secondary feedback path from the hydraulic actuator monitors the output to maintain constant control of the neutral position of that actuator. Attached to it is a neutral position indicator. Control and indication of the neutral position is essential for adjustment of the crusher jaws in relation to each other to compensate for wear and to control the size of the finished product.

Referring specifically to FIG. 2 the electro-dynamic drive is identified as 28. This drive is connected with the spool pilot valve 30 which in turn controls operation of the power valve 32. Hydraulic pressure is supplied to the passages identified as P while exhaust or return is had through the passage identified as R. The RD passages are return drain passages returning any fluid that may have leaked past the spool or the piston. It will thus be seen that oscillation or reciprocation of the spool 30 in turn causes reciprocation of the spool 32 of the power valve. Reciprocation of this later spool causes an alternate supply and return of fluid pressure to opposite sides of the hydraulic piston 22. Feedback for the electrical system is produced through the feedback transducers identified in FIG. 2. It will be understood that a hydraulic system will be provided to supply fiuid pressure to this valve control mechanism and the piston regulated thereby. This system can be of conventional design and construction and for simplicity has not been illustrated. Such a conventional system may include a drain tank of subatmospheric pressure, a supply tank of high pressure and a pump to remove iiuid from the drain tank and introduce it into the high pressure tank.

The hydraulic uid will generally have enough compressibility to take the shock that is produced when tramp iron is contained in the material that is fed to the Crusher. If desired, however, an accumulator such as that identified as 34 in FIG. l may be incorporated into the electrohydraulic actuator to increase the ability of this system to take up the shocks that may be thus produced.

With the arrangement of the invention a substantially greater speed of operation can be obtained with the jaw crusher than is possible with the conventional designs. This will enable the jaw Crusher to give the necessary production which would be heretofore had only with a combination jaw crusher and other type of crusher such as roller Crusher.

While I have illustrated and described a preferred embodiment of my invention it is to be understood that such is merely illustrative and not restrictive and that variations and modifications may be made therein without departing from the spirit and scope of the invention. I therefore do not wish to be limited to the precise details set forth but desire to avail myself of such changes as fall within the purview of my invention.

What I claim is:

1. A Crusher comprising a frame, a crushing jaw pivotally mounted on said frame adjacent the upper region 0f the jaw for pivotal movement thereof about its upper region to and from a crushing position, power driven means connected with the lower region of said jaw effective to oscillate the same about said pivotal mounting, said power driven means comprising an electro-hydeaulic exciter including an electric oscillator effective to produce an electric signal of a predetermined frequency, an electrodynamic driver effectively connected to receive the output signal of said oscillator, a piston-type hydraulic motor interposed between said frame and said jaw and pivotally connected with each jaw and hydraulic -control means operative to control the actuation of said motor, said hydraulic control means including a pilot valve and a power valve, said pilot valve being effective to control the operation of said power valve with said power valve in turn controlling the operation of said piston, said electro-dynamic driver being interconnected with said pilot valve and operative to operate the same at said predetermined frequency, said pilot valve in turn effecting operation of said power valve at said predetermined frequency with said power valve actuating said piston at the same frequency.

References Cited UNITED STATES PATENTS 1,847,083 3/1932 Flint 241--264 2,609,994 9/1952 Gaudie 241-264 X 2,955,460 10/l960 Stevens et al. 91-275 X 3,223,334 12/1965 Wuthrich 241-36 .T AMES M. MEISTER, Primary Examiner. 

